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Diroximel fumarate oral


Oral formulation of diroximel fumarate.

Drugs List

  • diroximel fumarate 231mg gastro-resistant capsules
  • VUMERITY 231mg gastro-resistant capsules
  • Therapeutic Indications


    Treatment of relapsing-remitting multiple sclerosis


    Start treatment gradually to minimise the occurrence of flushing and gastrointestinal adverse reactions.


    Initial dose: 231mg (1 capsule) twice a day. After 7 days, increase dose to 462mg (2 capsules) twice a day.

    Additional Dosage Information

    Reduce dose to 231mg twice a day to reduce the occurrence of adverse reactions. Resume the recommended dose of 462mg twice daily within 1 month.

    Missed doses Double dose should not be taken if a patient misses a dose. The missed dose may be taken only if they leave 4 hours between doses, otherwise the patient should wait until the next scheduled dose.


    Absolute lymphocyte count below 0.5 x 10 to the power of 9/L
    Children under 18 years
    Severe infection
    Progressive multifocal leukoencephalopathy (PML)

    Precautions and Warnings

    Antibodies to JC virus
    Moderate renal impairment
    Severe gastrointestinal disorder
    Severe hepatic impairment

    Treatment to be initiated and supervised by a specialist
    Capsules should not be opened or crushed
    A recent (within 3 months) MRI should be available prior to treatment
    Monitor renal and hepatic function before and during treatment
    Perform full blood count before treatment
    Monitor full blood counts every 3 months
    Advise patient that flushing reactions may occur
    Advise patient to report symptoms of infection immediately
    Advise patient to seek medical advice if severe flushing occurs
    Consider stopping if lymphocytes below 0.5x10 to power 9/L for 6 months
    Discontinue if anaphylactoid reaction occurs
    Discontinue if Progressive multifocal leukoencephalopathy (PML) develops
    Discontinue treatment if patient develops a serious infection
    Evaluate risk if lymphocyte count below 0.8x10 to power9/L for 6 months
    Female: Ensure adequate contraception during treatment
    Advise patient to report symptoms of herpes zoster urgently

    Prior to initiating treatment with diroximel fumarate, renal function (e.g. creatinine, blood urea nitrogen and urinalysis) should be assessed prior to treatment, after 3 and 6 months of treatment and 6 to 12 monthly thereafter as clinically indicated. Serum aminotransferases (e.g. alanine aminotransferase (ALT), aspartate aminotransferase (AST)) and total bilirubin levels are recommended to be assessed before treatment is initiated and during treatment as clinically indicated. Regular monitoring of absolute lymphocyte counts is recommended in lymphopenia patients with lymphocyte count below the normal limit due to an increased risk of Progressive Multifocal Leukoencephalopathy (PML). Magnetic resonance image (MRI) should be performed immediately in case of clinical suspicion of PML. Withhold treatment and perform John Cunningham Virus (JCV) DNA in cerobrospinal fluid (CSF) by quantitative polymerase chain reaction (PCR) methodology at the first sign or symptom suggestive of PML. Consider a short course of acetylsalicylic acid 75mg in patients who experience intolerable flushing.

    Cases of herpes zoster may occur at any time during the treatment. Monitor signs and symptoms of herpes zoster in particular when lymphocytopenia occurs simultaneously. Treat appropriately and withhold the treatment of diroximel fumarate in case of severe infections. Resume treatment only after the infections have been resolved.

    Always consider fanconi syndrome and perform appropriate examinations in case of unclear symptoms. Discontinuation of diroximel fumarate treatment in the early diagnosis of fanconi syndrome can prevent the onset of renal impairment and osteomalacia.

    Pregnancy and Lactation


    Diroximel fumarate is contraindicated during pregnancy.
    The manufacturer does not recommend using diroximel fumarate during pregnancy. The manufacturer advises that diroximel fumarate should only be used during pregnancy if the potential benefits outweigh the risk to the foetus. Animal studies have shown reproductive toxicity. Human data is limited and as such a potential risk cannot be ruled out.


    Diroximel fumarate is contraindicated during breastfeeding.
    The manufacturer advises that the patient either discontinues diroximel fumarate treatment or discontinues breastfeeding. The presence of diroximel fumarate in human breast milk and the effects on exposed infants are unknown.

    Side Effects

    Abdominal pain
    Alanine aminotransferase increased
    Aspartate aminotransferase increased
    Burning sensation
    Drug-induced liver injury
    Feeling hot
    Gastrointestinal disorder
    Herpes zoster
    Hot flushes
    Hypersensitivity reactions
    Progressive multifocal leukoencephalopathy (PML)
    Upper abdominal pain
    White blood cell count decreased


    It is strongly recommended that the UK National Poisons Information Service be consulted on cases of suspected or actual overdose where there is doubt over the degree of risk or about appropriate management.

    The following number will direct the caller to the relevant local centre (0844) 892 0111

    Information may be obtained if you have access to ToxBase the primary clinical toxicology database of the National Poisons Information Service. This is available via password on the internet ( ) or if this is unavailable at the backup site ( ).

    Reference Sources

    Summary of Product Characteristics: Vumerity 231mg gastro-resistant hard capsules. Biogen Idec Ltd. Revised November 2021.

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    Medscape UK | Univadis prescription drug monographs & interactions are based on FDB Multilex Content

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    FDB Disclaimer : FDB Multilex is intended for the use of healthcare professionals and is provided on the basis that the healthcare professionals will retain FULL and SOLE responsibility for deciding what treatment to prescribe or dispense for any particular patient or circumstance.